2002ApJ...572.1024N

We investigate orbital stability of terrestrial planets inside the habitable zones of three stellar systems, i.e., 51 Peg, 47 UMa, and HD 210277, with recently discovered giant planets. These systems have similar habitable zones; however, their giant planets have different masses and significantly different orbital parameters. It is shown that stable orbits of terrestrial planets exist in the entire habitable zone of 51 Peg as well as in the inner part of the habitable zone of 47 UMa, but no stable orbits are found in the habitable zone of HD 210277. The obtained results allow us to draw general conclusions on the existence of stable orbits in the habitable zones of newly found extra-solar planetary systems.